Emulsifying agent and process for making same



Patented Dec. 26, 1944 EMULSKFYING AGENT AND PROCESS FOR" G SAME JamesEarl Taylor, Louisville. Ky., assignor to The Procter and GambleCompany, Ivorydale,

Qhio, a corporation of Ohio No Drawing. Application August 26, 1942,Serial No. 458,275

3 Claims.

This invention relates to an improved emulsifylng agent and to a processfor making same.

The process employs lanolin, i. e. purified wool fat, as a basic rawmaterial, and includes the steps of saponifying the esters present inlanolin with litharge to form lead soaps and to liberate sterols,hydrogenating this mixture at high temperature and pressure to convertthe fatty acids of the lead soaps to the correspondin fatty alcohols,and freeing the hydrogenated product from metallic lead. The resultingproduct, which may be further purified if desired, consists largely ofcholesterol and fatty alcohols, and possesses ex cellent emulsifyingproperties which are superior to those of the original lanolin.

In application Serial No. 380,072, filed February 21, 1941, byRichardson and Taylor, now Patent No. 2,340,343, a process is describedand claimed which comprises, among other things, the conversion of fattyacids to the corresponding fatty cHa) by subjecting lead salts of thesefatty acid to contact with hydrogen at high temperature and pressure. Mypresent invention subjects selected raw materials to the general processdisclosed in that application in a manner such that a new and valuableproduct results As a specific example of one way in which my inventionmay be practiced, I first mix 21 parts of finely divided litharge withabout 100 to 120 parts of melted lanolin, having a saponification valueof 105, heat and agitate the mixture by blowing steam through it forseveral hours, or until the yellow color of the litharge hassubstantially disappeared, thus-forming lead soaps of fatty acids of theesters present in the lanolin. The resulting mixture, which includeslead soaps and unsaponiflable matter, 1. e., the sterols set free by thesaponification, is dried and is then placed in a strong stainless steelhydrogenation vessel in which an atmosphere of hydrogen is maintained. Ahydrogen pressure of about 2000 pounds per square inch is built up inthis vessel, the temperature of the reaction mixture i then raised toabout 340," C. and the hydrogen pressure is increased to about '4000pounds .per square inch, and the contents of the vessel are agitated tobring the hydrogen intointimate contact with the lanolin-lead soapmixture which is molten under these conditions. These conditions aremaintained for about one to three hours, after which the reactionmixture is cooled to about F. or lower,-the hydrogen pressure isrelieved, and the liquid reaction products are removed from the vessel,boiled with a dilute solution of hydrochloric acid, or otherwise treatedto remove free and combined lead, and washed or heated until free ofmineral acid. The product may then be filtered and dried if desired.

The resulting product, which contains cholesterol and other sterols, andalcohols corresponding to the fatty acids of the sterol esters of theoriginal lanolin, is an excellent emulsifying agent and as such isespecially useful in the preparation of cosmetic creams and ointments.

The conditions of temperature, pressure, time, etc., which are suitablefor the practice of my invention are not limited to those mentioned inthe foregoing example, as it is to be understood that the generalconditions described in application Serial No. 380,072 are applicable tothe instant process.

Preferred conditions for this process include maintenance of atemperature between about 240 C. and about 400 C. and a pressure inexcess of 2000 pounds per square inch. The alcohol forming reactionoccurs, although more slow- 1y, at temperatures below 240 C., down to180 C. at least. Likewise this reaction has been observed under suitabletemperature conditions at pressures as low as 500 pounds per squareinch. The time required for the reaction is usually relatively short. Inmany cases when temperature and pressure are within the preferred rangesapproximate equilibrium is reached within two or three hours, andsometimes the reaction goes substantially to completion within as shorta time as five minutes after reaching the preferred temperature.Continuation of the elevated reaction temperature and pressure andcontinued contact with hydrogen for several hours after completion ofthe alcohol-fuming reaction have not been found to influence the yieldsof the desired products to any appreciable extent.

An improved form of my product, possess1n8' greatly increased resistanceto oxidation, may be made by hydrogenating the above described productof my process at relatively low temperature and pressure, with the aidof a hydrogenation catalyst such as finely divided nickel, in such amanner as to saturate oleilnic double bonds according to well knownpractice. The product thus produced is a mixture of fatty alcohols andsterols corresponding to the fatty acids and sterols of lanolin, exceptthat these product components are less unsaturated and hence the producthas a lower iodine value and a firmer consistency at any temperaturebelow the complete melting point.

Having thus described my invention, what I claim and desire to secure byLetters Patent is:

1. An emulsifying agent comprising a mixture of sterols derived fromlanolin and alcohols corresponding to fatty acids of the esters oflanolin.

2. An emulsifying agent comprising a hydrogenated mixture, substantiallyfree from oleflnic double bonds, of sterols derived from lanolin andalcohols corresponding (except as to saturation of oleflnic doublebonds) to fatty acids of the esters of lanolin, said agent being formedby catalytic hydrogenation, at relatively low temperature and pressure,of the composition of claim 1.

3. A process of preparing an emulsifying agent. which comprises reactinglitharge with the esters of lanolin to form lead soaps of the esterfatty acids and to liberate sterols, and subjecting the resultingmixture, to reaction with hydrogen at elevated temperature and pressureto convert said fatty acids substantially to the corresponding alcohols.

JAMES EARL TAYLOR.

